This proposal introduces the concept of treating the wound as an in vivo tissue culture which is achieved by enclosing the wound in a sealed chamber which functions as an in vivo incubator. Tissue repair in swine will be improved by adding culture medium, transplants of suspensions of skin cells and growth factors. The growth factors will be administered topically as peptides or into wound tissue by particle mediated gene transfer. This study may open new avenues in the treatment of chronic wounds as well as wounds with excessive healing such as hypertrophic scars and keloids. The specific aims are: 1) to transplant keratinocyte suspensions and fibroblast suspensions in optimal cell numbers and to monitor with gene markers the repair process of epidermis and dermis; 2) to investigate if growth factors can be efficiently delivered by particle mediated gene transfer by in vivo or in vitro transfection (and transplantation) of autologous cells in order to provide an autocrine and paracrine source of peptide growth factors; 3) to investigate the effect of growth factors when delivered i) topically as peptides, ii) by in vivo gene transfer to wounds cells, or iii) by in vitro gene transfer to autologous cells which are transplanted to the wound as cell suspensions; and 4) to modify transgene persistence in the wound by transfection of cells with a resistant gene (neo) using an in vitro and in vivo selection environment.